SEASON OPENER: For tonight’s opening Season 8 installment, the blind auditions – this show’s best feature – begin again. The judges in the swivel chairs this time around (and around, and around) are stalwarts Blake Shelton and Adam Levine, both of whom have turned this NBC musical showcase into new levels of stardom, Pharell Williams, and, returning after some time off, Christina Aguilera. The new season will not resemble those high-concept promos from the Super Bowl, in which Aguilera lorded over a futuristic, Thunderdome-type arena competition. Though, honestly, I wish NBC had followed through and done precisely that…